In test equipment utilized for many purposes, such as measuring DC voltages over a plurality of ranges with a digital volt meter, measuring AC voltages over a plurality of ranges with a digital volt meter, counting frequencies, supplying a visual display of input signals on an oscilloscope, etc., it is generally necessary to supply a separate input for each function. Further, each input is generally connected through separate circuits which prepare the input signal for the function to be performed. In some prior art circuitry it is necessary to remove modules and substitute different modules before certain of these tests can be performed. Because it is necessary to change input terminals and/or modules when making a series of various test measurements, testing certain circuitry is cumbersome and tedious.